GM pioneers cheap collision detection, and yet another airbag

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Where else can you add an airbag? GM knows: It will add will add a no-cost, between-the-seats airbag that inflates out of the driver’s seat, protecting front seat occupants from banging into each other in side impacts. GM also introduced a dirt cheap ($295) collision warning system and lane departure warning system that uses a digital video camera mounted behind the rear view mirror rather than radar or multiple cameras. The combination shows American automakers are serious about offering safety devices that don’t cost an arm and leg.

The additional airbag restrains front seat passengers in side impacts and rollovers. It’s of special benefit when there’s both a driver and passenger and the collision is violent enough to slam the passengers together. The extra airbag provides separation. GM will start slowly, offering the front center airbag, as it’s called, on the 2013 Buick Enclave and GMC Acadia models with power seats, and on all GM Acadia, and Chevrolet Traverse SUVs.

GM says it spent three years working with seat beat-and-airbag supplier Takata to perfect the system. It’s unclear if GM/Takata will offer the center airbag to other automakers. In the past, automakers have had a gentleman’s agreement that technologies with clear lifesaving benefits should be made available (typically with royalties) throughout the industry.

The downsides are minor: It only works on two-passenger front-seat vehicles. It adds a couple pounds of weight to the vehicle and $100-$200 in manufacturer cost. With the front center airbag, it’s now possible to have a vehicle with two front airbags, four side airbags, two front knee airbags (keeps passengers from submarining), and side air curtain bags. For all their value, most safety experts still say the most bang for the buck comes from seat belts and electronic stability control.

Where the front center airbag is pure innovation, GM’s second announcement this week, the collision alert system, represents a breakthrough in cost savings. The combination forward collision alert and lane departure warning use a single digital camera and costs $295. On other vehicles, the forward collision alert system is part of adaptive cruise control systems that range from $1,000 (Ford) to $2,000-$3,000 (most other automakers). Lane departure warning on its own is typically in the $400 range. Here’s how GM made its version work, cheaply:

There’s a single digital camera mounted in the rear view mirror, facing forward. That’s also the location and technology behind existing lane departure warning systems. Raymond Kiefer, GM technical fellow for crash avoidance systems, says, “By combining a digital camera with state-of-the-art image processing algorithms, we’re able to estimate when a crash may be imminent.” The camera records 14 frames per second, looking for shapes that would be vehicles and pavement markings, and the algorithms compare four consecutive frames to understand closing rate and the potential for collision. It adds in information on whether the driver is on or off the throttle, and if the brakes are applied.

To get the price down to $295, GM made some compromises. There’s no adaptive cruise control (ACC), which usually uses costlier radar systems. The collision warning operates only at 25 mph and above. (Ford’s ACC system, which has collision warning, goes down to 20 mph, and others go down to 0 mph.) If it senses a potential collision, it pre-charges the brakes but doesn’t apply them, unlike ACC at higher speeds or Volvo City Safety, which emergency-stops cars below 18 mph in city settings. To do that, the option would likely cost more than $295. The lane departure warning works at 35 mph and above, which is typical.

A single dash-mounted module houses indicators for both forward collision warning and lane departure warning. There are green “vehicle ahead” and “lanes detected” icons, a flashing amber lane departure warning, and a flashing red collision alert. A warning beep sounds for each, more insistently for the collision alert. Based on the specs of the system, GM is likely to face negative customer feedback on the lane departure warning system. Drivers don’t like audible alerts or flashing indicators the passengers can see because the passengers hear the car telling the driver, “Hey, you screwed up again.” The more successful alerts gently vibrate the steering wheel or driver’s seat; researchers have suggested an LED “strobing” the driver’s line of sight (enough to be attention getting, not so much as to be blinding). According to GM, the LDW system is all-on or all-off; you can’t disable the audio only.

GM is starting slowly, offering the system on the 2012 GMC Terrain SUV. Rear-end collisions are common: 28% of the 6 million accidents reported to police last year. They are less serious than front or side collisions.

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T Marq

Leave to GM to continue their trend …. downward.

http://twitter.com/desaintpreux Highlander

That is really not a nice comment. I guess safety is a number one thing in every scenario. Sure it adds weight, but with the CRASH avoidance system, it surely is better than crashing. But if you crash!

http://twitter.com/deshbubc Desh Bandhu

Great use of creativity there! It is part creative instincts and part technology, and you have merged both beautifully

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